It has long been known that animals are sensitive to various audio frequencies within or without the range audible by man. Different species of animals are responsive to signals of widely different frequency ranges. The effects of audio signals on various species are also of widely different types. For instance, certain insects and in particular, moths, may be affected in their ability to fly. Certain animals lose their sense of direction. In the case of mosquitos, it is known that only the egg-laden female needing blood to feed her eggs will bite. Once mated, the female avoids the male. A device sending out a special audio signal which simulates the hum of a male mosquito can be very effective in clearing an area from the blood-thirsty female. Therefore, there is need for a versatile pest repelling apparatus which can be programmed to affect various types of pests by emitting simultaneously different audio signals directed toward different specific species of animals.